Storage tanks, in particular for the storage of oils, for example, gasoline or other fuels, usually have a double-walled design and have a surrounding liquid collecting channel. This is connected to a drain pipe, which, for example, leads into the sewage system. Rainwater usually accumulates in the liquid collecting channel and can then flow through the drain pipe. However, if the tank has a leak, liquid in the tank can escape at this point and also accumulate in the collecting channel. Apart from the loss of the stored product, such a leak also has ecological consequences, which is why a leak detection system is used for such tanks.
Sensor cables are often used to detect a leak in the tank wall. They are installed around the bottom or around the wall and capacitively detect liquid entering the cable. The operating life and the possibility of functionally checking such sensor cables are severely restricted, however, which results in a high replacement rate. This is accompanied by high costs.